Age-Related Influence of Bone Remodeling on Local Tissue Properties of Human Cortical Bone

With aging, cortical bone experiences deterioration in its mechanical competence, thus resulting in increased bone fragility. Studies have shown that the mechanical properties of cortical bone are significantly dependent on the quality and spatial arrangement of its constituents. Age-related changes have been observed in the mineral and collagen as well as the local microstructural properties of bone. Further, age-related changes in the material components and tissue architecture correlate significantly with decreases in bulk bone post-yield properties. Evidence indicates that these changes may be due in part to the bone remodeling process, which may alter material composition and spatial arrangement in a manner detrimental to the mechanical properties of the tissue.

This study was performed to determine if the bone remodeling process has an age-related effect on the micromechanical and compositional properties of cortical bone, and whether or not such changes are correlated with decreased post-yield properties in newly remodeled tissue. To investigate this issue, the micromechanical properties of secondary osteons (newly remodeled tissue) and interstitial tissue (biologically older tissue) were assessed using a microcompression test protocol. The compositional properties of the mineral and collagen components of osteonal and interstitial tissues were assessed using High Performance Liquid Chromatography, X-ray Diffraction analysis, and Fourier Transform Infrared Microscopy. Additionally, morphometric With aging, cortical bone experiences deterioration in its mechanical competence, thus resulting in increased bone fragility. Studies have shown that the mechanical properties of cortical bone are significantly dependent on the quality and spatial arrangement of its constituents. Age-related changes have been observed in the mineral and collagen as well as the local microstructural properties of bone. Further, age-related changes in the material components and tissue architecture correlate significantly with decreases in bulk bone post-yield properties. Evidence indicates that these changes may be due in part to the bone remodeling process, which may alter material composition and spatial arrangement in a manner detrimental to the mechanical properties of the tissue.

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Year

Entry

1989

Schaffler MB, Radin EL, Burr DB. Mechanical and morphological effects of strain rate on fatigue of compact bone. Bone. 1989;10(3):207-214.

2002

Wang X, Li X, Bank RA, Agrawal CM. Effects of collagen unwinding and cleavage on the mechanical integrity of the collagen network in bone. Calcif Tiss Int. August 2002;71(2):186-192.

1977

Nomura S, Hiltner A, Lando JB, Baer E. Interaction of water with native collagen. Biopolymers. 1977;16:231-246.

2002

Boivin G, Meunier PJ. The degree of mineralization of bone tissue measured by computerized quantitative contact microradiography. Calcif Tiss Int. June 2002;70(6):503-511.

1976

Parfitt AM. The actions of parathyroid hormone on bone: relation to bone remodeling and turnover, calcium homeostasis, and metabolic bone disease: part I of IV parts: mechanisms of calcium transfer between blood and bone and their cellular basis: morphological and kinetic approaches to bone turnover. Metabolism. July 1976;25(7):809-844.